A typica typicall soil soil corro corrosio sion n is aggrav aggravated ated under under which which of the followi following ng conditions a. b. c. d.
Q.2 Q.2
Impact testing Hydrostatic testing PWHT Pneumatic te testing
Bran Branch chin ing, g, Tra Trans nsgr gran anul ular ar and and ini initi tiat ate e from from wit withi hin n the the mate materi rial al.. Dagg Dagger er shape shaped, d, interg intergra ranul nular ar and and init initiat iate e form form within within the mater material ial.. Dagg Dagger er shap shaped ed,, oxi oxide de fill filled ed and and ini initi tiat ate e for form m the the surf surfac ace. e. Dagger sha shap ped, cle clea an and and inter tergra granular. ar.
Erosi Erosion on/Co /Corro rrosi sion on miti mitiga gatio tion n can can be achie achieve ved d by a. b. c. d.
Q.6
Thermal fatigue. Mechanical fatigue. Vibration fatigue. Both a and b.
Ther Therma mall fat fatig igue ue crac cracks ks usua usuall lly y are are a. b. c. d.
Q.5 Q.5
and and high high resi resist stiv ivit ity y of of soi soil. l. and and low low res resis isti tiv vity ity of of soi soil. l. and and high high resi resist stiv ivit ity y of of soi soil. l. and and low low res resis isti tiv vity ity of of soi soil. l.
Reduct Reduction ion in in likeli likelihoo hood d of brittle brittle fract fracture ure can be be obtain obtained ed by by perfor performing ming a. b. c. d.
Q.4 Q.4
mo moistu isture re cont conten entt mo moistu isture re cont conten entt mo moistu isture re cont conten entt mo moistu isture re cont conten entt
Typi Typica call “hig “high h cyc cycle le fati fatigu gue e is: is: a. b. c. d.
Q.3
Hgh Hgh Hgh Hgh Low Low Low Low
Incr Increa easi sing ng the the pip pipe e dia diame mete terr to to dec decre reas ase e vel veloc ocit ity y Incr Increa easi sing ng sur surfa face ce hard hardne ness ss by by usin using g hard harder er all alloy oys s or hard hard fac facin ing g Using co corrosion re resistant al alloys All of the above.
“Clam “Clam shel shell” l” type type crack crack failu failure re havin having g concen concentric tric rings rings called called “beach “beach marks” showing “waves” of crack propagation is typically the description of
a. b. c. d.
Q.7
Resistance to sulphidation is generally achieved by a. b. c. d.
Q.8
Upgrading to higher nickel alloys Upgrading to higher chromium alloys Upgrading to higher copper based alloys All of the above.
Characteristic Chloride SCC in Austenitic S.S. generally will be a. b. c. d.
Transgranular, branching and aggravated by higher temperature. Intergranular and unidirectional (straight) and aggravated by low temperature Independent of chloride content None of the above
Caustic embrittlement may be reduced/prevented by:: a. b. c. d.
Conducting PWHT. Upgrading to Nickel alloys. Using High hardness & High strength steels. Both a and b.
Q.10 High temperature hydrogen attack is typically due to a. Methane gas formation. b. Wet H2S formation c. Temper embrittlement d. Presence of Molybdenum in alloy steels.
Q.11 Recording on a data sheet of an indication that exceeds the reject flaw size criteria and needs to be corrected isa. b. c. d.
Recordable indication Reportable indication Notable indication None of above
Q.12 A sub –surface terrace and step-like crack with basic orientation parallel to the base metal surface caused by tensile stresses in thickness direction is called a. b. c. d.
Q.13 “Slag inclusion” is not found in welding performed by a. b. c. d.
Q.14
SMAW SAW FCAW GMAW
Most applicable method for sub-surface porosity is a. UT
b. PT
c. ET
d. RT
Q.15 VT is most conveniently performed placing an eye a. b. c. d.
Within 6” – 24” with angle less than 30° with the surface Within 6’’-24’’ with angle not less than 30° with surface Beyond 24’’ with angle less than 30° Beyond 24’’with angle not less than 30°
Q.16 A clear radiography film has density of a. 4
b. 0
c. 2
d. infinity
Q.17 In UT examination, a. b. c. d.
A - scan shows cross-sectional elevation view B - scan shows cross-sectional elevation view C-scan shows cross-sectional elevation view none of above
Q.18 Steels with CE greater than 0.55% typically require: a. b. c.
Preheating only Pre-heating & PWHT No pre- heating or PWHT
d.
PWHT only
Q.19 A method to assure that PWHT was performed satisfactorily is a. b. c. d.
Hardness testing of weld & HAZ Radiography of weld &HAZ PT or MT of weld &HAZ UT of weld & haz
Q.20 Welding process that has very high metal deposition rate is a. b. c. d.
